Portable power sources are used in, for example, military applications, aviation applications, wilderness and personal survival applications, hiking and camping applications, and disaster relief efforts. For example, portable battery packs exist for carrying in a backpack or for wearing on the body. These battery packs, however, can be heavy and inconvenient to access and connect to devices requiring electrical power. Further, some applications may require that the appearance of the battery pack blend with the environment in which they are used. Current battery packs, however, might not offer flexibility of appearance or the consumer is forced to buy one battery pack for one environment and a different battery pack for a different environment.